1 /* This is the Assembler Pre-Processor
2 Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 97, 98, 1999
3 Free Software Foundation, Inc.
5 This file is part of GAS, the GNU Assembler.
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* Modified by Allen Wirfs-Brock, Instantiations Inc 2/90 */
23 /* App, the assembler pre-processor. This pre-processor strips out excess
24 spaces, turns single-quoted characters into a decimal constant, and turns
25 # <number> <filename> <garbage> into a .line <number>\n.file <filename>
26 pair. This needs better error-handling. */
29 #include "as.h" /* For BAD_CASE() only */
33 #define const /* empty */
37 /* Whether we are scrubbing in m68k MRI mode. This is different from
38 flag_m68k_mri, because the two flags will be affected by the .mri
39 pseudo-op at different times. */
40 static int scrub_m68k_mri
;
42 /* The pseudo-op which switches in and out of MRI mode. See the
43 comment in do_scrub_chars. */
44 static const char mri_pseudo
[] = ".mri 0";
46 #if defined TC_ARM && defined OBJ_ELF
47 /* The pseudo-op for which we need to special-case `@' characters.
48 See the comment in do_scrub_chars. */
49 static const char symver_pseudo
[] = ".symver";
50 static const char * symver_state
;
54 static const char symbol_chars
[] =
55 "$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
57 #define LEX_IS_SYMBOL_COMPONENT 1
58 #define LEX_IS_WHITESPACE 2
59 #define LEX_IS_LINE_SEPARATOR 3
60 #define LEX_IS_COMMENT_START 4
61 #define LEX_IS_LINE_COMMENT_START 5
62 #define LEX_IS_TWOCHAR_COMMENT_1ST 6
63 #define LEX_IS_STRINGQUOTE 8
64 #define LEX_IS_COLON 9
65 #define LEX_IS_NEWLINE 10
66 #define LEX_IS_ONECHAR_QUOTE 11
68 #define LEX_IS_DOUBLEDASH_1ST 12
71 #define LEX_IS_DOUBLEBAR_1ST 13
73 #define IS_SYMBOL_COMPONENT(c) (lex[c] == LEX_IS_SYMBOL_COMPONENT)
74 #define IS_WHITESPACE(c) (lex[c] == LEX_IS_WHITESPACE)
75 #define IS_LINE_SEPARATOR(c) (lex[c] == LEX_IS_LINE_SEPARATOR)
76 #define IS_COMMENT(c) (lex[c] == LEX_IS_COMMENT_START)
77 #define IS_LINE_COMMENT(c) (lex[c] == LEX_IS_LINE_COMMENT_START)
78 #define IS_NEWLINE(c) (lex[c] == LEX_IS_NEWLINE)
80 static int process_escape
PARAMS ((int));
82 /* FIXME-soon: The entire lexer/parser thingy should be
83 built statically at compile time rather than dynamically
84 each and every time the assembler is run. xoxorich. */
87 do_scrub_begin (m68k_mri
)
93 scrub_m68k_mri
= m68k_mri
;
95 lex
[' '] = LEX_IS_WHITESPACE
;
96 lex
['\t'] = LEX_IS_WHITESPACE
;
97 lex
['\r'] = LEX_IS_WHITESPACE
;
98 lex
['\n'] = LEX_IS_NEWLINE
;
99 lex
[';'] = LEX_IS_LINE_SEPARATOR
;
100 lex
[':'] = LEX_IS_COLON
;
104 lex
['"'] = LEX_IS_STRINGQUOTE
;
107 lex
['\''] = LEX_IS_ONECHAR_QUOTE
;
110 #ifdef SINGLE_QUOTE_STRINGS
111 lex
['\''] = LEX_IS_STRINGQUOTE
;
115 /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop
116 in state 5 of do_scrub_chars must be changed. */
118 /* Note that these override the previous defaults, e.g. if ';' is a
119 comment char, then it isn't a line separator. */
120 for (p
= symbol_chars
; *p
; ++p
)
122 lex
[(unsigned char) *p
] = LEX_IS_SYMBOL_COMPONENT
;
123 } /* declare symbol characters */
125 for (c
= 128; c
< 256; ++c
)
126 lex
[c
] = LEX_IS_SYMBOL_COMPONENT
;
128 #ifdef tc_symbol_chars
129 /* This macro permits the processor to specify all characters which
130 may appears in an operand. This will prevent the scrubber from
131 discarding meaningful whitespace in certain cases. The i386
132 backend uses this to support prefixes, which can confuse the
133 scrubber as to whether it is parsing operands or opcodes. */
134 for (p
= tc_symbol_chars
; *p
; ++p
)
135 lex
[(unsigned char) *p
] = LEX_IS_SYMBOL_COMPONENT
;
138 /* The m68k backend wants to be able to change comment_chars. */
139 #ifndef tc_comment_chars
140 #define tc_comment_chars comment_chars
142 for (p
= tc_comment_chars
; *p
; p
++)
144 lex
[(unsigned char) *p
] = LEX_IS_COMMENT_START
;
145 } /* declare comment chars */
147 for (p
= line_comment_chars
; *p
; p
++)
149 lex
[(unsigned char) *p
] = LEX_IS_LINE_COMMENT_START
;
150 } /* declare line comment chars */
152 for (p
= line_separator_chars
; *p
; p
++)
154 lex
[(unsigned char) *p
] = LEX_IS_LINE_SEPARATOR
;
155 } /* declare line separators */
157 /* Only allow slash-star comments if slash is not in use.
158 FIXME: This isn't right. We should always permit them. */
161 lex
['/'] = LEX_IS_TWOCHAR_COMMENT_1ST
;
166 lex
['\''] = LEX_IS_STRINGQUOTE
;
167 lex
[';'] = LEX_IS_COMMENT_START
;
168 lex
['*'] = LEX_IS_LINE_COMMENT_START
;
169 /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but
170 then it can't be used in an expression. */
171 lex
['!'] = LEX_IS_LINE_COMMENT_START
;
175 lex
['-'] = LEX_IS_DOUBLEDASH_1ST
;
178 lex
['|'] = LEX_IS_DOUBLEBAR_1ST
;
181 /* must do this is we want VLIW instruction with "->" or "<-" */
182 lex
['-'] = LEX_IS_SYMBOL_COMPONENT
;
184 } /* do_scrub_begin() */
186 /* Saved state of the scrubber */
188 static int old_state
;
189 static char *out_string
;
190 static char out_buf
[20];
191 static int add_newlines
;
192 static char *saved_input
;
193 static int saved_input_len
;
194 static char input_buffer
[32 * 1024];
195 static const char *mri_state
;
196 static char mri_last_ch
;
198 /* Data structure for saving the state of app across #include's. Note that
199 app is called asynchronously to the parsing of the .include's, so our
200 state at the time .include is interpreted is completely unrelated.
201 That's why we have to save it all. */
208 char out_buf
[sizeof (out_buf
)];
213 const char * mri_state
;
215 #if defined TC_ARM && defined OBJ_ELF
216 const char * symver_state
;
223 register struct app_save
*saved
;
225 saved
= (struct app_save
*) xmalloc (sizeof (*saved
));
226 saved
->state
= state
;
227 saved
->old_state
= old_state
;
228 saved
->out_string
= out_string
;
229 memcpy (saved
->out_buf
, out_buf
, sizeof (out_buf
));
230 saved
->add_newlines
= add_newlines
;
231 if (saved_input
== NULL
)
232 saved
->saved_input
= NULL
;
235 saved
->saved_input
= xmalloc (saved_input_len
);
236 memcpy (saved
->saved_input
, saved_input
, saved_input_len
);
237 saved
->saved_input_len
= saved_input_len
;
239 saved
->scrub_m68k_mri
= scrub_m68k_mri
;
240 saved
->mri_state
= mri_state
;
241 saved
->mri_last_ch
= mri_last_ch
;
242 #if defined TC_ARM && defined OBJ_ELF
243 saved
->symver_state
= symver_state
;
246 /* do_scrub_begin() is not useful, just wastes time. */
251 return (char *) saved
;
258 register struct app_save
*saved
= (struct app_save
*) arg
;
260 /* There is no do_scrub_end (). */
261 state
= saved
->state
;
262 old_state
= saved
->old_state
;
263 out_string
= saved
->out_string
;
264 memcpy (out_buf
, saved
->out_buf
, sizeof (out_buf
));
265 add_newlines
= saved
->add_newlines
;
266 if (saved
->saved_input
== NULL
)
270 assert (saved
->saved_input_len
<= (int) (sizeof input_buffer
));
271 memcpy (input_buffer
, saved
->saved_input
, saved
->saved_input_len
);
272 saved_input
= input_buffer
;
273 saved_input_len
= saved
->saved_input_len
;
274 free (saved
->saved_input
);
276 scrub_m68k_mri
= saved
->scrub_m68k_mri
;
277 mri_state
= saved
->mri_state
;
278 mri_last_ch
= saved
->mri_last_ch
;
279 #if defined TC_ARM && defined OBJ_ELF
280 symver_state
= saved
->symver_state
;
286 /* @@ This assumes that \n &c are the same on host and target. This is not
313 /* This function is called to process input characters. The GET
314 parameter is used to retrieve more input characters. GET should
315 set its parameter to point to a buffer, and return the length of
316 the buffer; it should return 0 at end of file. The scrubbed output
317 characters are put into the buffer starting at TOSTART; the TOSTART
318 buffer is TOLEN bytes in length. The function returns the number
319 of scrubbed characters put into TOSTART. This will be TOLEN unless
320 end of file was seen. This function is arranged as a state
321 machine, and saves its state so that it may return at any point.
322 This is the way the old code used to work. */
325 do_scrub_chars (get
, tostart
, tolen
)
326 int (*get
) PARAMS ((char *, int));
331 char *toend
= tostart
+ tolen
;
335 register int ch
, ch2
= 0;
337 /*State 0: beginning of normal line
338 1: After first whitespace on line (flush more white)
339 2: After first non-white (opcode) on line (keep 1white)
340 3: after second white on line (into operands) (flush white)
341 4: after putting out a .line, put out digits
342 5: parsing a string, then go to old-state
343 6: putting out \ escape in a "d string.
344 7: After putting out a .appfile, put out string.
345 8: After putting out a .appfile string, flush until newline.
346 9: After seeing symbol char in state 3 (keep 1white after symchar)
347 10: After seeing whitespace in state 9 (keep white before symchar)
348 11: After seeing a symbol character in state 0 (eg a label definition)
349 -1: output string in out_string and go to the state in old_state
350 -2: flush text until a '*' '/' is seen, then go to state old_state
352 12: After seeing a dash, looking for a second dash as a start of comment.
355 13: After seeing a vertical bar, looking for a second vertical bar as a parallel expression seperator.
359 /* I added states 9 and 10 because the MIPS ECOFF assembler uses
360 constructs like ``.loc 1 20''. This was turning into ``.loc
361 120''. States 9 and 10 ensure that a space is never dropped in
362 between characters which could appear in a identifier. Ian
363 Taylor, ian@cygnus.com.
365 I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works
366 correctly on the PA (and any other target where colons are optional).
367 Jeff Law, law@cs.utah.edu.
369 I added state 13 so that something like "cmp r1, r2 || trap #1" does not
370 get squashed into "cmp r1,r2||trap#1", with the all important space
371 between the 'trap' and the '#1' being eliminated. nickc@cygnus.com */
373 /* This macro gets the next input character. */
377 ? * (unsigned char *) (from++) \
378 : (saved_input = NULL, \
379 fromlen = (*get) (input_buffer, sizeof input_buffer), \
380 from = input_buffer, \
381 fromend = from + fromlen, \
384 : * (unsigned char *) (from++))))
386 /* This macro pushes a character back on the input stream. */
388 #define UNGET(uch) (*--from = (uch))
390 /* This macro puts a character into the output buffer. If this
391 character fills the output buffer, this macro jumps to the label
392 TOFULL. We use this rather ugly approach because we need to
393 handle two different termination conditions: EOF on the input
394 stream, and a full output buffer. It would be simpler if we
395 always read in the entire input stream before processing it, but
396 I don't want to make such a significant change to the assembler's
408 if (saved_input
!= NULL
)
411 fromend
= from
+ saved_input_len
;
415 fromlen
= (*get
) (input_buffer
, sizeof input_buffer
);
419 fromend
= from
+ fromlen
;
424 /* The cases in this switch end with continue, in order to
425 branch back to the top of this while loop and generate the
426 next output character in the appropriate state. */
431 if (*out_string
== '\0')
448 as_warn (_("end of file in comment"));
457 while ((ch
= GET ()) == '*')
462 as_warn (_("end of file in comment"));
480 else if (ch
>= '0' && ch
<= '9')
484 while (ch
!= EOF
&& IS_WHITESPACE (ch
))
490 out_string
= "\n\tappfile ";
492 out_string
= "\n\t.appfile ";
499 while (ch
!= EOF
&& ch
!= '\n')
508 /* We are going to copy everything up to a quote character,
509 with special handling for a backslash. We try to
510 optimize the copying in the simple case without using the
511 GET and PUT macros. */
516 for (s
= from
; s
< fromend
; s
++)
519 /* This condition must be changed if the type of any
520 other character can be LEX_IS_STRINGQUOTE. */
528 if (len
> toend
- to
)
532 memcpy (to
, from
, len
);
541 as_warn (_("end of file in string: inserted '\"'"));
546 else if (lex
[ch
] == LEX_IS_STRINGQUOTE
)
551 #ifndef NO_STRING_ESCAPES
558 else if (scrub_m68k_mri
&& ch
== '\n')
560 /* Just quietly terminate the string. This permits lines like
561 bne label loop if we haven't reach end yet
578 /* Handle strings broken across lines, by turning '\n' into
605 #if defined(IGNORE_NONSTANDARD_ESCAPES) | defined(ONLY_STANDARD_ESCAPES)
607 as_warn (_("Unknown escape '\\%c' in string: Ignored"), ch
);
609 #else /* ONLY_STANDARD_ESCAPES */
611 /* Accept \x as x for any x */
613 #endif /* ONLY_STANDARD_ESCAPES */
616 as_warn (_("End of file in string: '\"' inserted"));
635 while (ch
!= '\n' && ch
!= EOF
);
643 /* OK, we are somewhere in states 0 through 4 or 9 through 11 */
650 #if defined TC_ARM && defined OBJ_ELF
651 /* We need to watch out for .symver directives. See the comment later
653 if (symver_state
== NULL
)
655 if ((state
== 0 || state
== 1) && ch
== symver_pseudo
[0])
656 symver_state
= symver_pseudo
+ 1;
660 /* We advance to the next state if we find the right
662 if (ch
!= '\0' && (*symver_state
== ch
))
664 else if (*symver_state
!= '\0')
665 /* We did not get the expected character, or we didn't
666 get a valid terminating character after seeing the
667 entire pseudo-op, so we must go back to the beginning. */
671 /* We've read the entire pseudo-op. If this is the end
672 of the line, go back to the beginning. */
677 #endif /* TC_ARM && OBJ_ELF */
680 /* We want to have pseudo-ops which control whether we are in
681 MRI mode or not. Unfortunately, since m68k MRI mode affects
682 the scrubber, that means that we need a special purpose
684 if (mri_state
== NULL
)
686 if ((state
== 0 || state
== 1)
687 && ch
== mri_pseudo
[0])
688 mri_state
= mri_pseudo
+ 1;
692 /* We advance to the next state if we find the right
693 character, or if we need a space character and we get any
694 whitespace character, or if we need a '0' and we get a
695 '1' (this is so that we only need one state to handle
696 ``.mri 0'' and ``.mri 1''). */
699 || (*mri_state
== ' '
700 && lex
[ch
] == LEX_IS_WHITESPACE
)
701 || (*mri_state
== '0'
707 else if (*mri_state
!= '\0'
708 || (lex
[ch
] != LEX_IS_WHITESPACE
709 && lex
[ch
] != LEX_IS_NEWLINE
))
711 /* We did not get the expected character, or we didn't
712 get a valid terminating character after seeing the
713 entire pseudo-op, so we must go back to the
719 /* We've read the entire pseudo-op. mips_last_ch is
720 either '0' or '1' indicating whether to enter or
722 do_scrub_begin (mri_last_ch
== '1');
725 /* We continue handling the character as usual. The
726 main gas reader must also handle the .mri pseudo-op
727 to control expression parsing and the like. */
736 as_warn (_("end of file not at end of a line; newline inserted"));
745 case LEX_IS_WHITESPACE
:
750 while (ch
!= EOF
&& IS_WHITESPACE (ch
));
756 /* Preserve a single whitespace character at the
757 beginning of a line. */
766 || IS_LINE_SEPARATOR (ch
))
770 /* In MRI mode, we keep these spaces. */
778 /* If we're in state 2 or 11, we've seen a non-white
779 character followed by whitespace. If the next character
780 is ':', this is whitespace after a label name which we
781 normally must ignore. In MRI mode, though, spaces are
782 not permitted between the label and the colon. */
783 if ((state
== 2 || state
== 11)
784 && lex
[ch
] == LEX_IS_COLON
796 goto recycle
; /* Punted leading sp */
798 /* We can arrive here if we leave a leading whitespace
799 character at the beginning of a line. */
805 /* Optimize common case by skipping UNGET/GET. */
806 PUT (' '); /* Sp after opco */
815 /* In MRI mode, we keep these spaces. */
820 goto recycle
; /* Sp in operands */
825 /* In MRI mode, we keep these spaces. */
831 state
= 10; /* Sp after symbol char */
835 #ifdef LABELS_WITHOUT_COLONS
842 /* We know that ch is not ':', since we tested that
843 case above. Therefore this is not a label, so it
844 must be the opcode, and we've just seen the
845 whitespace after it. */
849 PUT (' '); /* Sp after label definition. */
856 case LEX_IS_TWOCHAR_COMMENT_1ST
:
865 if (ch2
!= EOF
&& IS_NEWLINE (ch2
))
868 while (ch2
!= EOF
&& ch2
!= '*');
873 if (ch2
== EOF
|| ch2
== '/')
876 /* This UNGET will ensure that we count newlines
882 as_warn (_("end of file in multiline comment"));
891 if (state
== 9 || state
== 10)
897 case LEX_IS_STRINGQUOTE
:
900 /* Preserve the whitespace in foo "bar" */
905 /* PUT didn't jump out. We could just break, but we
906 know what will happen, so optimize a bit. */
919 case LEX_IS_ONECHAR_QUOTE
:
922 /* Preserve the whitespace in foo 'b' */
931 as_warn (_("end of file after a one-character quote; \\0 inserted"));
939 as_warn (_("end of file in escape character"));
943 ch
= process_escape (ch
);
945 sprintf (out_buf
, "%d", (int) (unsigned char) ch
);
947 /* None of these 'x constants for us. We want 'x'. */
948 if ((ch
= GET ()) != '\'')
950 #ifdef REQUIRE_CHAR_CLOSE_QUOTE
951 as_warn (_("Missing close quote: (assumed)"));
957 if (strlen (out_buf
) == 1)
967 out_string
= out_buf
;
973 if (state
== 9 || state
== 10)
981 /* Roll out a bunch of newlines from inside comments, etc. */
987 /* fall thru into... */
989 case LEX_IS_LINE_SEPARATOR
:
995 case LEX_IS_DOUBLEDASH_1ST
:
1002 /* read and skip to end of line */
1007 while (ch
!= EOF
&& ch
!= '\n');
1010 as_warn (_("end of file in comment; newline inserted"));
1017 case LEX_IS_DOUBLEBAR_1ST
:
1024 /* Reset back to state 1 and pretend that we are parsing a line from
1025 just after the first white space. */
1031 case LEX_IS_LINE_COMMENT_START
:
1032 /* FIXME-someday: The two character comment stuff was badly
1033 thought out. On i386, we want '/' as line comment start
1034 AND we want C style comments. hence this hack. The
1035 whole lexical process should be reworked. xoxorich. */
1051 if (state
== 0 || state
== 1) /* Only comment at start of line. */
1061 while (ch
!= EOF
&& IS_WHITESPACE (ch
));
1064 as_warn (_("end of file in comment; newline inserted"));
1068 if (ch
< '0' || ch
> '9' || state
!= 0 || startch
!= '#')
1070 /* Not a cpp line. */
1071 while (ch
!= EOF
&& !IS_NEWLINE (ch
))
1074 as_warn (_("EOF in Comment: Newline inserted"));
1079 /* Loks like `# 123 "filename"' from cpp. */
1084 out_string
= "\tappline ";
1086 out_string
= "\t.appline ";
1087 PUT (*out_string
++);
1092 /* All insns end in a char for which LEX_IS_SYMBOL_COMPONENT is true.
1093 Trap is the only short insn that has a first operand that is
1094 neither register nor label.
1095 We must prevent exef0f ||trap #1 to degenerate to exef0f ||trap#1 .
1096 We can't make '#' LEX_IS_SYMBOL_COMPONENT because it is already
1097 LEX_IS_LINE_COMMENT_START. However, it is the only character in
1098 line_comment_chars for d10v, hence we can recognize it as such. */
1099 /* An alternative approach would be to reset the state to 1 when
1100 we see '||', '<'- or '->', but that seems to be overkill. */
1101 if (state
== 10) PUT (' ');
1103 /* We have a line comment character which is not at the
1104 start of a line. If this is also a normal comment
1105 character, fall through. Otherwise treat it as a default
1107 if (strchr (tc_comment_chars
, ch
) == NULL
1108 && (! scrub_m68k_mri
1109 || (ch
!= '!' && ch
!= '*')))
1112 && (ch
== '!' || ch
== '*' || ch
== '#')
1117 case LEX_IS_COMMENT_START
:
1118 #if defined TC_ARM && defined OBJ_ELF
1119 /* On the ARM, `@' is the comment character.
1120 Unfortunately this is also a special character in ELF .symver
1121 directives (and .type, though we deal with those another way). So
1122 we check if this line is such a directive, and treat the character
1123 as default if so. This is a hack. */
1124 if ((symver_state
!= NULL
) && (*symver_state
== 0))
1131 while (ch
!= EOF
&& !IS_NEWLINE (ch
));
1133 as_warn (_("end of file in comment; newline inserted"));
1138 case LEX_IS_SYMBOL_COMPONENT
:
1141 /* This is a symbol character following another symbol
1142 character, with whitespace in between. We skipped
1143 the whitespace earlier, so output it now. */
1153 /* This is a common case. Quickly copy CH and all the
1154 following symbol component or normal characters. */
1156 && mri_state
== NULL
1157 #if defined TC_ARM && defined OBJ_ELF
1158 && symver_state
== NULL
1165 for (s
= from
; s
< fromend
; s
++)
1169 ch2
= * (unsigned char *) s
;
1172 && type
!= LEX_IS_SYMBOL_COMPONENT
)
1177 /* Handle the last character normally, for
1182 if (len
> (toend
- to
) - 1)
1183 len
= (toend
- to
) - 1;
1189 memcpy (to
, from
, len
);
1197 case 8: *to
++ = *from
++;
1198 case 7: *to
++ = *from
++;
1199 case 6: *to
++ = *from
++;
1200 case 5: *to
++ = *from
++;
1201 case 4: *to
++ = *from
++;
1202 case 3: *to
++ = *from
++;
1203 case 2: *to
++ = *from
++;
1204 case 1: *to
++ = *from
++;
1214 /* Some relatively `normal' character. */
1217 state
= 11; /* Now seeing label definition */
1219 else if (state
== 1)
1221 state
= 2; /* Ditto */
1223 else if (state
== 9)
1225 if (lex
[ch
] != LEX_IS_SYMBOL_COMPONENT
)
1228 else if (state
== 10)
1240 /* We have reached the end of the input. */
1241 return to
- tostart
;
1244 /* The output buffer is full. Save any input we have not yet
1249 saved_input_len
= fromend
- from
;
1254 return to
- tostart
;